ADR 0003: CI coverage policy

Status

Accepted

Context

The project targets 100% test coverage for production code. CI must collect coverage on every run, surface results on pull requests, and prevent regressions.

Decision

1. Tooling: Use pytest-cov (dev dependency) with [tool.coverage.*] configuration in pyproject.toml.
2. Local and CI entry point: just test-cov runs integration tests under tests/ and pydocks/features/ with coverage for the pydocks package.
3. Threshold: CI enforces 100% line coverage via COVERAGE_FAIL_UNDER (default). Tests run under coverage run for accurate measurement.
4. CI reporting:
5. Markdown coverage summary in the GitHub Actions job summary (irongut/CodeCoverageSummary)
6. Pull request comment via py-cov-action/python-coverage-comment-action (Python 3.14 matrix job)
7. coverage.xml and htmlcov/ uploaded as workflow artifacts
8. Scope: just test runs tests without the coverage gate for faster local iteration.

Consequences

• Coverage regressions fail CI on every matrix Python version.
• Pull requests show line-level coverage without external services.
• Developers use just test-cov before opening PRs that touch production code.